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Metamorphic fluids and transtension in the Cantabrian Mountains of northern Spain: an application of the conodont colour alteration index

Published online by Cambridge University Press:  01 May 2009

J. G. M. Raven
Affiliation:
Binnenweg 46, 2264 MK Leidschendam, The Netherlands
Ben A. Van Der Pluijm*
Affiliation:
Department of Geological Sciences, University of Michigan, 1006 C. C. Little Building, Ann Arbor, MI 48109, USA
*
Corresponding author.

Abstract

Conodont colour alteration index (CAI) values from Upper Paleozoic rocks in the Cantabrian zone of northern Spain show that temperatures during Hercynian metamorphism locally exceeded 300 °C. Various temperature domains have been defined, which are generally separated by fundamental structures. These domains do not correspond with the tripartite subdivision based on stratigraphic analysis.

The observed CAI values of conodonts are in general agreement with the mineral paragenesis. Areas with high CAI values display extensive alteration and mineralization, and where CAI values exceed 4–4.5 (>200 °C) slaty cleavage has developed.

The Cantabrian zone is an area of very low grade metamorphism, where peak conditions were reached in Upper Carboniferous to Lower Permian times. The characteristics of the metamorphism and its spatial relationship with major faults suggest that fluids were the main source for regional heating and that fluid transport was focussed along crustal-scale structural features.

The overall deformation regime in this part of the Variscan orogen of western Europe is interpreted to be large-scale transtension. This is in agreement with earlier proposed models for the formation of Upper Palaeozoic basins in this area.

Type
Articles
Copyright
Copyright © Cambridge University Press 1986

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References

Aldridge, R. J. 1984. Thermal metamorphism of the Silurian strata of the Oslo region, assessed by conodont colour. Geological Magazine 121, 347–9.CrossRefGoogle Scholar
Aller, J. & Brime, C. 1983. Deformacion y metamorfismo en la parte sur de la Cuenca Carbonifera Central (NO de España). Resumenes del X Congreso internacional de Estratigrafia y Geologia del Carbonifero, Madrid.Google Scholar
Arboleya, M. L. 1981. La enstructura del manto del Esla (Cordillera Cantabrica, Leon). Boletin de Geologico y Minero España 92, 1940.Google Scholar
Arthaud, F. & Matte, P. 1977. Late Paleozoic strike–slip faulting in southern Europe and northern Africa: Results of a right-lateral shear zone between the Appalachians and the Urals. Geological Society of America Bulletin 88, 1305–20.2.0.CO;2>CrossRefGoogle Scholar
Bastida, F., Marcos, A., Arboleya, M. L. & Mendez, I. 1976. La unidad de Peña Corada y su relacion con el manto del esla (Zone Cantabrica, NW de España). Breviora geologica Asturica 10, 4955Google Scholar
BergstrÖM, S. M. 1981. Conodonts as paleotemperature tools in Ordovician rocks of the Caledonides and adjacent areas in Scandinavia and the British Isles. Geologiska Föreningens i Stockholm Förhandlingar 102, 377392.CrossRefGoogle Scholar
Brime, C. 1985. A diagenesis to metamorphism transition in the Hercynian of north-west Spain. Mineralogical Magazine 49, 481–4.CrossRefGoogle Scholar
Capdevila, R. 1967. Extension du métamorphisme régional Hercynienne dans le Nord-ouest de l'Espagne (Galice orientale, Asturias, Leon). Comtes rendues sommaires de la Société Géologique France, 277–9.Google Scholar
Capdevila, R. 1969. Le métamorphisme régional progressif et les granites dans le segment Hercynien de Galice Nord orientale (NW de l'Espagne). Thèse Université de Montpellier.Google Scholar
Epstein, A. G., Epstein, J. B., & Harris, L. D. 1977. Conodont color alteration index to organic metamorphism. Professional Paper of the U.S. Geological Survey No. 995, 27 pp.CrossRefGoogle Scholar
Etheridge, M. A., Wall, V. J. & Vernon, R. H. 1983. The role of the fluid phase during regional metamorphism and deformation. Journal of Metamorphic Petrology 1, 205–26.CrossRefGoogle Scholar
Evers, H. J. 1967. Geology of the Leonides between the rivers Bernesga and Porma (Cantabrian Mountains, NW Spain). Leidse Geologische Mededelingen 41, 83151.Google Scholar
Ferry, J. M. 1983. Regional metamorphism of the Vassalboro Formation, south-central Maine, USA: a case study of the role of fluid in metamorphic petrogenesis. Journal of the Geological Society of London 140, 551–76.CrossRefGoogle Scholar
Flajs, G. 1980. Conodont metamorphism: grain size–temperature relationship (abstract). Abhandlungen der Geologischen Bundesanstalt (Wien) 35, 213.Google Scholar
Fyfe, W. S., Price, N. J. & Thompson, A. B. 1978. Fluids in the Earth's Crust. Amsterdam, Elsevier: 383 pp.Google Scholar
Harland, W. B. 1971. Tectonic transpression in Caledonian Spitsbergen. Geological Magazine 108, 2742.CrossRefGoogle Scholar
Harris, A. G. 1979. Conodont color alteration, an organomineral metamorphic index, and its application to Appalachian basin geology. In Aspects of Diagenesis (ed. Scholle, P. A. Schluger, P. R.), pp. 316. Special Publication of the Society of Economic Paleontologists and Mineralogists no. 26.CrossRefGoogle Scholar
Heward, A. P. & Reading, H. G. 1980. Deposits associated with a Hercynian to late Hercynian continental strike–slip system, Cantabrian Mountains, northern Spain. In Sedimentation in Oblique Slip Mobile Zones (eds.) Ballance, P. F. and Reading, H. G., pp. 105–26. Special Publication of the International Association of Sedimentologists no. 4.CrossRefGoogle Scholar
Julivert, M. 1971. Décollement tectonics in the Hercynian Cordillera of NW Spain. American Journal of Science 270, 129.CrossRefGoogle Scholar
Julivert, M. 1981. A cross-section through the northern part of the Iberian Massif. In The Variscan Orogen in Europe (ed. Zwart, H. J. and Dornsiepen, U. F.), Geologie en Mijnbouw 60, 107128.Google Scholar
Koopmans, B. N. 1962. The sedimentary and structural history of the Valsurvio Dome, Cantabrian Mountains, Spain, Leidse Geologische Mededelingen 28, 121232.Google Scholar
Legall, F. D., Barnes, C. R. & Macqueen, R. W. 1981. Thermal maturation, burial history and hotspot development, Paleozoic strata of southern Ontario–Quebec, from conodont and acritarch colour alteration studies. Bulletin of Canadian Petroleum Geology 29, 492539.Google Scholar
Loeschke, J. 1982. Late Hercynian igneous rocks of the southeastern Cantabrian Mountains (NW Spain). In Subsidenz-Entwicklung im Kantabrischen Variszikum und an passiven Kontinen-talranden der Kreide. Teil I. Variszikum (ed. Kullman, J., R., Schonenberg J., Wiedmann). Neues Jahrbuch für Geologie und Palaontologie Abhandlungen 163, 260272.Google Scholar
Loeschke, J. & Zeidler, N. 1983. Early Paleozoic sills in the Cantabrian Mountains (Spain) and their geotectonic environment. Neues Jahrbuch für Geologie und Palaontologie Monatschefte 1983, 419–39.Google Scholar
Lotze, F. 1945. Zur Gliederung der Varisziden der Iberischen Meseta. Geotektonische Forschung 6, 7892.Google Scholar
Luque, C. & MartinezGarcia, E. Garcia, E. 1983. Depositos minerales en el Carbonifero en la Cordillera Cantabrica. In Carbonifero y Permico de España (ed. Martinez Diaz, C.), pp. 163–77. Instituto Geologico y Minero de España.Google Scholar
Maas, K. 1974. The geology of the Liebana area, Cantabrian Mountains, Spain: deposition and deformation in a flysch area. Leidse Geologische Mededelingen 49, 379465.Google Scholar
Marcos, A. 1968. Nota sobre el significado de la ‘Leon line’. Breviora Geologica Asturica 12, 15.Google Scholar
Martinez, F. J. & GilIbarguchi, I. Ibarguchi, I. 1983. El metamorfismo en el Macizo Iberico. In Libro Jubilar J. M. Rios. Geologia de España. Tomo 1. Madrid (ed. Comba, J. A.), pp. 555–68. Instituto Geologico y Minero de España.Google Scholar
Perez Estun, A. 1978. Estratigrafia y estructura de la rama S. de la Zona Asturoccidental–Leonesa. Memoria del Instituto Geologico y Minero de España 92, 1149.Google Scholar
Pietzner, H., Vahl, J., Werner, H. & Ziegler, W. 1968. Zur chemischen Zusammensetzung und Mikromorphologie der Conodonten. Palaeontographica 128, 115–52.Google Scholar
Price, L. C. 1983. Geologic time as a parameter in organic metamorphism and vitrinite reflectance as an absolute paleogeothermometer. Journal of Petroleum Geology 6, 538.CrossRefGoogle Scholar
Price, L. C. 1985. Geologic time as a paramenter in organic metamorphism and vitrinite reflectance as an absolute paleogeothermometer: Reply. Journal of Petroleum Geology 8, 233–40.CrossRefGoogle Scholar
Raven, J. G. M 1983. Conodont biostratigraphy and depositional history of the Middle Devonian to Lower Carboniferous in the Cantabrian zone (Cantabrian Mountains, Spain). Leidse Geologische Mededelingen 52, 265339.Google Scholar
Rupke, J. 1965. The Esla nappe, Cantabrian Mountains (Spain). Leidse Geologische Mededelingen 32, 174.Google Scholar
Rupke, N. A. 1977. Growth of an ancient deep-sea fan. Journal of Geology 85, 725–44.CrossRefGoogle Scholar
Sandberg, C. A. & Gutschick, R. C. 1984. Distribution, microfauna and source-rock potential of Mississippian Delle phosphatic member of Woodman Formation and equivalents, Utah and adjacent states. In Hydrocarbon Source Rocks of the Greater Rocky Mountain Region: Denver, Colorado (ed. Woodward, J., Meissner, F. F., Clayton, J. C.), pp. 135–78. Rocky Mountain Association of Geologists.Google Scholar
Sanderson, D. J. & Marchini, W. R. D. 1984. Transpression. Journal of Structural Geology 6, 449–58.CrossRefGoogle Scholar
Savage, J. F. 1967. Tectonic analysis of Lechada and Curavacas synclines, Yuso Basin, NW Spain. Leidse Geologische Mededelingen 39, 193247.Google Scholar
Savage, J. F. 1979. The Hercynian Orogeny in the Cantabrian Mountains, N. Spain. Krystallinikum 14, 91108Google Scholar
Savage, J. F. 1981. Geotectonic cross-sections through the Cantabrian Mountains, northern Spain. In The Variscan Orogen in Europe (ed. Zwart, H. J. Dornsiepen, U. F.). Geologie en Mijnbouw 60, 35.Google Scholar
Savage, J. F. & Boschma, D. 1980. Geological maps of the southern Cantabrian Mountains (Spain). Leidse Geologische Mededelingen 50, 75114.Google Scholar
SchÖNlaub, H. P. 1979. Das Palaozoikum in Osterreich. Abhandlungen der Geologischen Bundesanstalt (Wien) 33, 124.Google Scholar
Sibson, R. H., Moore, J. M. & Rankin, A. H. 1975. Seismic pumping – a hydrothermal fluid transport mechanism. Journal of the Geological Society of London 131, 653–9.CrossRefGoogle Scholar
Sjerp, N. 1967. Geology of the San Isidro–Porma area (Cantabrian Mountains, Spain). Leidse Geologische Mededelingen 39, 55128.Google Scholar
Van Adrichem, Boogaert, H., A. 1967. Devonian and Lower Carboniferous conodonts of the Cantabrian Mountains (Spain) and their stratigraphic application. Leidse Geologische Mededlingen 39, 129–92.Google Scholar
Van Der Pluijm, B. A. & Kaars-Sijpesteijn, C. H. 1984. Chlorite–mica aggregates: morphology, orientation, development and bearing on cleavage formation in very-low-grade rocks. Journal of Structural Geology 6, 399407.CrossRefGoogle Scholar
Van Der Pluijm, B. A., Savage, J. F. & Kaars-Sijpesteijn, C. H. 1986. Variation in fold geometry in the Yuso Basin, northern Spain: implications for the deformation regime. Journal of Structural Geology 8 (in press).Google Scholar
Van Veen, J. 1965. The tectonic and stratigraphic history of the Cardaño area, Cantabrian Mountains, northwest Spain, Leidse Geologische Mededelingen 35, 45104.Google Scholar
Wagner, R. H. 1971. Carboniferous nappe structures in northwestern Palencia (Spain). In The Carboniferous of Northwest Spain (ed. Wagner, R. H.), pp. 431–56. Trabajos de Geologia de la Universidad de Oviedo no. 4.Google Scholar
Wardlaw, B. R. & Harris, A. G. 1984. Conodont-based thermal maturation of Paleozoic rocks in Arizona. Bulletin of the American Association of Petroleum Geologists 68, 1101–6.Google Scholar
Zwart, H. J. & Dornsiepen, U. F. 1978. The tectonic framework of central and western Europe. In Key-notes of the MEGS-II (Amsterdam, 1978) (ed. van Loon, A. J.), Geologie en Mijnbouw 57, 627–54.Google Scholar